A liquid crystal display device and an organic EL (Electroluminescence) display device having a liquid crystal element or a light-emitting element in each pixel are represented as a typical example of a display device. These display devices have a liquid crystal element or an organic light-emitting element (hereinafter, referred to as a light-emitting element) in each of a plurality of pixels formed over a substrate. A liquid crystal element and a light-emitting element respectively have a liquid crystal or a layer (hereinafter, referred to as an organic layer or an EL layer) including an organic compound between a pair of electrodes and are operated by applying a voltage or supplying current between the pair of electrodes.
Addition of flexibility to a substrate of such a display device allows production of a flexible display device. A flexible display device is called a sheet display and has attracted much attention as a wearable display device attachable to clothes or a part of a body, for example. For instance, Japanese patent application publication No. 2015-26055 discloses a display device utilizing, as a flexible substrate, a substrate including fibers containing silicon rubber and the like. This display device can be folded due to its flexibility.